I had a lot to say and still have more! : )
I'm sorry that you were sick in the winter and were in the hospital, but, yes, the fact that you saw her on the weekends, helped. Earlier you had said 'we,' so, I'm assuming there was another person home with her when you were in the hospital. This last time you went away, no one was in the house and someone was feeding and giving her water, scooping the boxes, etc., but not staying in the house.
I believe this is most likely a behavioral problem, but it's always best to first bring her to her vet for a complete physical and a fecal sample analysis, just to rule out anything medical.
Also, try to feed one brand of food in both dry and canned. The food should be grain-free and not include any artificial flavors, colors and/or preservatives. Some good suggestions are Wellness, Wellness CORE, EVO, and many others in your pet store. Just read the label and make sure real meat is the first ingredient and it doesn't include any of the above.
If you try the Feliway and incorporate all the suggestions I recommended and she's still soiling outside the box, discuss with your vet, a prescription anti-anxiety/anti-depressant medication at a low dose. I prefer to recommend prescription medication as a last resort. One that is good for this problem (mainly urination, thought), is called Clomicalm. Here is more information:
I hope all will be well with Gracie and this problem is resolved, soon; however, remember, that it might take a little while, especially if you're making some changes.
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